Manufacturing apparatus of absorbent article and manufacturing method of absorbent article

ABSTRACT

An apparatus for manufacturing an absorbent article includes a guide mechanism having a feeding portion for feeding an elastic member. The feed portion is alternately movable in a first direction and a second direction, and the elastic member is brought into contact with a web conveyed in a machine direction and is ananged in a waveform. The first direction is from a center portion of the web to a first end portion in a cross direction crossing the machine direction. The second direction is from the center portion to a second end portion opposite to the first end portion. A distance between the feeding portion and a nip point at which the elastic member comes in contact with the web is largest when the nip point exceeds a position in the waveform where an angle between the machine direction and a tangent to the waveform is largest.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a manufacturing apparatus of anabsorbent article and a manufacturing method of an absorbent article forarranging an elastic member on a web by using a guide unit guiding theelastic member, the web being conveyed in a predetermined direction in astate in which components forming one part of the absorbent article aresequentially arranged.

2. Description of the Related Art

Conventionally, the manufacturing process of an absorbent article suchas a disposable diaper widely uses a method of arranging a filiformelastic member (rubber) having stretching properties in positionscorresponding to leg circumferential regions and a crotch region, inorder to improve the fittingness of the leg circumferential regions andthe crotch region to a target wearing the article (for example, a humanbody).

Specifically, in the manufacturing process, a filiform elastic member isarranged in a waveform on a web in which components of absorbentarticles, such as back sheets or absorbent sheets, are sequentiallyarranged. That is, the filiform elastic member is arranged in a waveformon a crosswise-flow web in which the longitudinal direction of theabsorbent article is arranged in a cross direction (CD) crossing aconveyance direction (Machine Direction (MD)) of the web. Accordingly,the absorbent articles each provided with gathers corresponding to theshapes of the leg circumferential regions and the crotch region can becontinuously manufactured.

As such a method of arranging a filiform elastic member in a waveform ona web being conveyed, known is a method in which a guide member guidingthe elastic member to a feeding position on the web is driven by a cam(for example, see Japanese Unexamined Patent Application Publication No.H3-33201 (page 4, FIGS. 6 and 7)).

In addition, known is a method in which a guide member guiding anelastic member to a feeding position on a web is reciprocated in crossdirections crossing a conveyance direction of the web (for example,Japanese Patent Application Publication No. 2006-141642 (page 10, FIG.1)).

In this regard, the feeding position of the elastic member from theguide member may be positioned exactly at a nip point where an elasticmember and a web are brought into contact with each other by beingtogether held between press rollers provided above and under the web,and this positioning may be made by bringing the guide member intodirect contact with the nip point. In fact, however, such positioning isnot practical because of the layout of the apparatus. For this reason,designing a profile of an apparatus that moves a guide member isrequired to consider this distance.

However, the above-described conventional manufacturing apparatus of anabsorbent article has the following problem. Specifically, this problemis that the profile of a device such as a cam has to be preciselydesigned in consideration of a distance between a nip point and afeeding position in order to accurately arrange an elastic member in adesired position on a web which is being conveyed at high speed.

SUMMARY OF THE INVENTION

The present invention has been made in light of the foregoing situation.Accordingly, an object of the present invention is to provide amanufacturing apparatus of an absorbent article and a manufacturingmethod of an absorbent article which are capable of arranging an elasticmember in a desired position on a web which is being conveyed at highspeed without requiring precise profile designing.

To solve the above-described problem, the present invention includes thefollowing aspects. Firstly, a first aspect of the present inventionprovides a manufacturing apparatus (elastic member fixing apparatus 100)of an absorbent article in which, with a guide unit (arm member 220)including a feeding portion (tip end portion 222) from which an elasticmember (elastic member 6′) is fed and guiding the elastic member, thefeeding portion is moved alternately in a first direction (firstdirection Da) and a second direction (second direction Db) so that theelastic member is brought into contact with a web and is arranged in apredetermined waveform (gather waveform), the web (second web 7B orthird web 7C) being conveyed in a predetermined direction in a state inwhich components forming one part of the absorbent article (absorbentarticle 1) are sequentially arranged, the first direction directing froma center portion of the web to a first end portion (first end portion 7a) in a cross direction (cross direction CD) crossing the predetermineddirection (conveyance direction MD), and the second direction directingfrom the center portion to a second end portion (second end portion 7 b)that is an end portion opposite to the first end portion. In themanufacturing apparatus, in a planar view of the web, when a nip point(N1, N2) at which the elastic member comes in contact with the webexceeds a position in the predetermined waveform where an angle (angleθ, φ) between the predetermined direction and a tangent to thepredetermined waveform is largest, a distance (feeding distance LN1,LN2) between the feeding portion and the nip point is largest.

The aspect of the present invention can provide a manufacturingapparatus of an absorbent article and a manufacturing method of anabsorbent article, in which an elastic member can be easily arrangedalong a certain waveform determined in advance in a desired position ona web which is being conveyed at high speed.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view showing an absorbent article according tothe present embodiment.

FIG. 2 is a view for illustrating one part of a manufacturing method ofan absorbent article according to the present embodiment.

FIG. 3 is a perspective view showing an elastic member fixing apparatusaccording to the present embodiment.

FIG. 4 is a top view (a view seen in the direction of the arrow A inFIG. 3) showing the elastic member fixing apparatus according to thepresent embodiment.

FIG. 5 is a side view (a view seen in the direction of the arrow B inFIG. 3) showing the elastic member fixing apparatus according to thepresent embodiment.

FIG. 6 is a schematic view showing how a front leg gather is arranged inthe top view (the view seen in the direction of the arrow A in FIG. 3)shown in FIG. 4.

DESCRIPTION OF THE PREFERRED EMBODIMENT

A manufacturing method of an absorbent article according to the presentinvention will be described below by referring to the drawings.Specifically, the description will be given of the following points: (1)Configuration of Absorbent Article, (2) Manufacturing Method ofAbsorbent Article, (3) Configuration of Elastic Member Fixing Apparatus,(4) Configuration of Shaking Guide Mechanism, (5) Operation of ElasticMember Fixing Apparatus, (6) Advantages and Effects, and (7) OtherEmbodiments.

In the following description of the drawings, same or similar referencesymbols are given to denote same or similar portions. However, it shouldbe noted that the drawings are schematic and ratios of dimensions andthe like are different from actual ones.

Therefore, specific dimensions and the like should be determined bytaking into consideration the following description. Moreover, as amatter of course, also among the drawings, there are included portionsin which dimensional relationships and ratios are different from eachother.

(1) Configuration of Absorbent Article

Firstly, a configuration of an absorbent article according to thepresent embodiment will be described by referring to the drawings. FIG.1 is a perspective view showing an absorbent article according to thepresent embodiment. In the present embodiment, an absorbent article 1 isa disposable diaper for adults.

As shown in FIG. 1, the absorbent article 1 is mainly formed of a liquidpermeable front sheet 2 which comes in contact with a skin of a targetwearing the article (hereinafter, a wearer), a back sheet 3 provided atthe outer side of the front sheet 2, and an absorber 4 which is providedbetween the front sheet 2 and the back sheet 3, and absorbs dejecta fromthe wearer.

In addition, a liquid impermeable waterproof sheet (unillustrated) isprovided between the back sheet 3 and the absorber 4. That is, theabsorber 4 is provided between the front sheet 2 and the waterproofsheet.

As the front sheet 2, employed is a nonwoven fabric, a perforatedplastic film, or the like. As the back sheet 3, employed is a nonwovenfabric. As the absorber 4, employed is ground pulp, a mixture of groundpulp and high absorbent polymer particles, or the like. As thewaterproof sheet, employed is a plastic, a nonwoven fabric, a mixedsheet of a plastic film and a nonwoven fabric, or the like.

The absorbent article 1 has a front waistline region 10 corresponding toa front waistline of the wearer, a back waistline region 20corresponding to a back waistline of the wearer, and a crotch region 30corresponding to a crotch of the wearer.

The front waistline region 10 and the back waistline region 20 areintegrated by connecting portions 40. A waist gather 5 made of afiliform rubber or the like having stretching properties is provided atthe peripheries of the front waistline region 10 and the back waistlineregion 20. The waist gather 5 is formed of a front waist gather 5 apositioned in the front waistline region 10 and a back waist gather 5 bpositioned in the back waistline region 20. A waistline opening region50 is formed between the front waist gather 5 a and the back waistlinegather 5 b.

The front waistline region 10 and the back waistline region 20 havestretching properties in a conveyance direction MD (MD direction) of afirst web 7A forming the front sheet 2 and a second web 7B (see, FIG. 2)forming the back sheet 3. For example, the front waistline region 10 andthe back waistline region 20 may be elastic in the conveyance directionMD by providing the waist gather 5 or may be elastic in the conveyancedirection MD by forming the front waistline region 10 and the backwaistline region 20 themselves with elastic sheets.

The crotch region 30 is provided between the front waistline region 10and the back waistline region 20. Leg gathers 6, each formed of afiliform rubber having stretching properties or the like, are formed onboth sides of the crotch region 30. The leg gather 6 is formed of afront leg gather 6 a positioned closer to the front waistline region 10and a back leg gather 6 b positioned closer to the back waistline region20. Leg circumferential opening regions 60 are formed at portions whichare between the front leg gather 6 a and the back leg gather 6 b and onthe both sides of the crotch region 30.

The crotch region 30 is elastic in the cross direction CD (CD direction)crossing the conveyance direction MD. For example, the crotch region 30may be elastic in the cross direction CD by providing the leg gather 6therein or may be elastic in the cross direction CD by forming thecrotch region 30 itself with an elastic sheet.

Regions Sk shown in FIG. 1 show positions corresponding to inguinalregions of the wearer when the wearer wears the diaper. A method ofarranging the front leg gather 6 a in the regions Sk will be describedin (5) Operation of Elastic Member Fixing Apparatus.

(2) Manufacturing Method of Absorbent Article

Next, a configuration of a manufacturing method of an absorbent articleaccording to the present embodiment will be described by referring tothe drawings. FIG. 2 is a view for illustrating a part of amanufacturing method of an absorbent article according to the presentembodiment.

As shown in FIG. 2, the manufacturing method of an absorbent articleincludes at least a component mounting process, a leg circumferenceforming process, a folding process, a connecting process, and a cuttingprocess. Note that processes of conveying webs in the conveyancedirection MD (predetermined direction) are included between theindividual processes by using an unillustrated conveyance apparatus (forexample, a belt conveyance apparatus). The webs conveyed here are theliquid permeable first web 7A used to form the front sheet 2, the liquidimpermeable second web 7B used to form the back sheet 3, and a third web7C which is of the same material as that of the second web 7B and usedto form the back sheet 3.

(2-1) Component Mounting Process

In the component mounting process S1, components constituting theabsorbent article 1, such as the elastic member, the third web 7C, thewaterproof sheet (unillustrated), and the absorber 4, are mounted on thesecond web 7B.

Specifically, firstly, the elastic member 5′ forming the waist gather 5in a stretched state is linearly mounted in the positions correspondingto the front waistline region 10 and the back waistline region 20 on thesecond web 7B. That is, the elastic member 5 a′ forming the front waistgather 5 a and the elastic member 5 b′ forming the back waist gather 5 bare mounted in the positions corresponding to the front waistline region10 and the back waistline region 20 on the second web 7B. With thisconfiguration, the waist gather 5 (the front waistline gather 5 a andthe back waist gather 5 b) is formed in the positions corresponding tothe front waistline region 10 and the back waistline region 20 on thesecond web 7B.

Secondly, the third web 7C is mounted on the second web 7B. At thistime, the elastic member 6′ forming the leg gather 6 in the stretchedstate is arranged in the position corresponding to the crotch region 30on the second web 7B and the third web 7C while swinging at apredetermined cycle in the cross direction CD. Then, the elastic member6′ is held between the second web 7B and the third web 7C to form theleg gather 6 (the front leg gather 6 a and the back leg gather 6 b).

Note that the second web 7B and the third web 7C which hold the elasticmember 6′ therebetween are pressed by an upper press roller 130A and alower press roller 130B which will be described later.

The elastic member 6 a′ forming the front leg gather 6 a and the elasticmember 6 b′ forming the back leg gather 6 b form a large ring portion 6Cand a small ring portion 6 d which has a smaller size in the crossdirection CD than that of the large ring portion 6 c.

As described above, after arranging the elastic member 6′ on the secondweb 7B and the third web 7C, the second web 7B and the third web 7C arepressed by the upper press roller 130A and the lower press roller 130B.At this time, if a position in which the small ring portion 6 d isdesigned to be formed is not pressed, the elastic member 6′ is not fixedin the designed position on the web. The elastic member 6′ is arrangedin the stretched state, so that it contracts in the position where theelastic member 6′ is not fixed on the web and thus forms a substantiallystraight line from a predetermined arranged shape. In this manner, thesmall ring portion 6 d is formed.

The same holds for a case where an adhesive is not applied to thedesigned position. In the position where the adhesive is not designed tobe applied, the elastic member 6′ is not fixed on the web. Accordingly,the small ring portion 6 d can be similarly formed.

Thirdly, the waterproof sheet (unillustrated) and the absorber 4 aremounted on the second web 7B and the third web 7C with the elasticmember 6′ being held therebetween so as to be uniformly spaced in theconveyance direction MD. The waterproof sheet may be mounted on thesecond web 7B and the third web 7C in a state being connected with theabsorber 4 in advance, or may be mounted on the second web 7B and thethird web 7C in a state being separated from the absorber 4.

Fourthly, the first web 7A forming the front sheet 2 overlaps the secondweb 7B and the third web 7C on which the components forming theabsorbent article 1 are mounted.

Note that, the component mounting process S1 does not necessarily haveto be performed in the order of the first step to the fourth step. Theorder may be changed if needed.

(2-2) Leg Circumference Forming Process

In the leg circumference forming process S2, after the componentmounting process S1, an inner circumferential side of the large ringportion 6 c is cut out on the second web 7B and the first web 7A withthe components being held therebetween (hereinafter, a composite web 7)to form the leg circumference opening region 60 (so-called, a leg hole).

(2-3) Folding Process

In the folding process S3, after the leg circumference forming processS2, the composite web 7 is folded in two along the center line CL whichpasses through the center of the composite web 7 in the cross directionCD and extends in the conveyance direction MD. That is, a side edge 10Aof the composite web 7 corresponding to the front waistline region 10and a side edge 20A of the composite web 7 corresponding to the backwaistline region 20 overlap each other being flush with each other.

(2-4) Connecting Process

In the connecting process S4, after the folding process S3,predetermined regions 40A corresponding to the connecting portions 40 ofthe absorbent article are connected with supersonic treatment or heattreatment. The predetermined regions 40A show both sides of a virtualline SL in the conveyance direction MD, which extends in the crossdirection CD and shows a position designed to be cut.

(2-5) Cutting Process

In the cutting process S5, after the connecting process S4, thecomposite web 7 with the predetermined regions 40A connected is cutalong the virtual line SL. In doing so, the absorbent article 1 isformed.

(3) Configuration of Elastic Member Fixing Apparatus

Next, the configuration of an elastic member fixing apparatus(manufacturing apparatus of an absorbent article) which is used in theabove-described component mounting process will be described byreferring to the drawings. FIG. 3 is a perspective view showing anelastic member fixing apparatus according to the present embodiment.FIG. 4 is a top view (a view seen in the direction of the arrow A inFIG. 3) showing the elastic member fixing apparatus according to thepresent embodiment. FIG. 5 is a side view (a view seen in the directionof the arrow B in FIG. 3) showing the elastic member fixing apparatusaccording to the present embodiment.

As shown in FIGS. 3 to 5, the elastic member fixing apparatus 100 swingsthe elastic member 6′ forming the leg gather 6 in the cross direction CDat a predetermined cycle so as to arrange the elastic member 6′ betweenthe second web 7B and the third web 7C. That is, the elastic memberfixing apparatus 100 arranges the elastic member 6′ in a curved statebetween the second web 7B and the third web 7C to form the leg gather 6(the front leg gather 6 a and the back leg gather 6 b).

The elastic member fixing apparatus 100 includes at least a web feedingmechanism (unillustrated), a gather feeding mechanism (unillustrated),an adhesive applying mechanism 110, a swinging guide mechanism 120(guide arm portion), and a press roller mechanism 130.

(3-1) Web Feeding Mechanism

The web feeding mechanism sequentially feeds a web from a jumbo roll.Specifically, the web feeding mechanism has an upper web feedingmechanism which sequentially feeds the third web 7C from a web jumboroll 7C′ and a lower web feeding mechanism which sequentially feeds thesecond web 7B from a second web jumbo roll 7B′.

The upper web feeding mechanism and the lower web feeding mechanismsequentially feed the second web 7B and the third web 7C to the pressroller mechanism 130 through rollers 140A and 140B which rotate aroundrotation shafts (unillustrated) provided along the cross direction CD.

(3-2) Gather Feeding Mechanism

The gather feeding mechanism sequentially feeds the elastic member 6′forming the leg gather 6 from a jumbo roll. Specifically, the gatherfeeding mechanism has a front gather feeding mechanism whichsequentially feeds the elastic member 6 a′ forming the front leg gather6 a from a jumbo roll (unillustrated) and a back gather feedingmechanism which sequentially feeds the elastic member 6 b′ forming theback leg gather 6 b from a jumbo roll (unillustrated).

The front gather feeding mechanism and the back gather feeding mechanismsequentially feed the leg gather 6 to the press roller mechanism 130through feed rollers 150A and 150B which rotate around the rotationshafts (unillustrated) provided along the cross direction CD andline-dividing rollers 151A and 151B which divide the elastic member 6 a′and the elastic member 6 b′.

(3-3) Adhesive Applying Mechanism

The adhesive applying mechanism is a spray-type device for applying anadhesive (for example, a hot-melt adhesive) onto a web. Specifically,the adhesive applying mechanism 110 has an upper adhesive applyingmechanism 110A which applies an adhesive onto the third web 7C and alower adhesive applying mechanism 110B which applies an adhesive ontothe second web 7B.

Note that the upper adhesive applying mechanism 110A applies an adhesiveonto a surface of the third web 7C except the center portion thereof. Onthe other hand, the lower adhesive applying mechanism 110B applies anadhesive onto an entire surface of the second web 7B.

(3-4) Shaking Guide Mechanism

The swinging guide mechanism 120 swings the elastic member 6′ formingthe leg gather 6 in the cross direction CD at a predetermined cycle. Theswinging guide mechanism 120 has a first swinging guide mechanism 200Awhich swings the elastic member 6 a′ forming the front leg gather 6 aand a second swinging guide mechanism 200B which swings the elasticmember 6 b′ forming the back leg gather 6 b. The swinging guidemechanism 120 will be described later in detail.

(3-5) Press Roller Mechanism

The press roller mechanism 130 presses the second web 7B and the thirdweb 7C with the elastic member 6′ being held between the second web 7Band the third web 7C. Specifically, the press roller mechanism 130 hasan upper press roller 130A which comes in contact with the third web 7Cand a lower press roller 130B which comes in contact with the second web7B.

The upper press roller 130A rotates around the rotation shaft 131Aprovided along the cross direction CD. Similarly, the lower press roller130B rotates around the rotation shaft 131B provided along the crossdirection CD. The elastic member 6′ is guided by the swinging guidemechanism 120 to a position where the upper press roller 130A and thelower press roller 130B come closest to each other.

(4) Configuration of Shaking Guide Mechanism

Next, the configuration of the swinging guide mechanism 120 which is acharacteristic of the present invention will be described by referringto FIGS. 3 to 5.

The first swinging guide mechanism 200A and the second swinging guidemechanism 200B basically have similar configurations, except that armmembers 22 to be described later have different lengths. For thisreason, the first swinging guide mechanism 200A and the second swingingguide mechanism 200B are described together as the swinging guidemechanism 120.

As shown in FIGS. 3 to 5, the swinging guide mechanism 120 has a motor210 with a rotation shaft 211, an arm member 220 which guides theelastic member 6′ to a predetermined position in the cross direction CDbetween the second web 7B and the third web 7C, the rotation shaft 211,and a base 221 of the arm member 220.

(4-1) Motor

The motor 210 is formed of a servomotor which is operated by acontroller in which a program is inputted. This program is capable ofcausing the elastic member 6′ to have a predetermined extensionmagnification and arranging the elastic member 6′ in a desired layoutaccording to a conveyance speed (V1) of the web.

The program operating the motor 210 of the first swinging guidemechanism 200A is different from the program operating the motor 210 ofthe second swinging guide mechanism 200B. That is, the predeterminedextension magnification and the layout in the front leg gather 6 a aredifferent from the predetermined extension magnification and the layoutin the back leg gather 6 b.

The motor 210 is attached to a base plate 213 through a bracket 212(see, FIG. 4). In the base plate 213, the motor 210 is movable in thecross direction CD if needed. When D1 denotes a distance to the pressroller mechanism 130 from the base plate 213 equipped with the motor 210of the first swinging guide mechanism 200A, and D2 denotes a distance tothe press roller mechanism 130 from the base plate 213 equipped with themotor 210 of the second swinging guide mechanism 200B, the distances D1and D2 are different from each other.

(4-2) Arm Member

The arm member 220 forms a tapered plate shape from the base 222 to thetip end portion 222. It is preferable that the arm member 220 behorizontally arranged (see, FIG. 5).

The arm member 220 is formed by using a metal steel plate. For example,the arm member 220 is formed by using a stainless steel plate.

The tip end portion 222 of the arm member 220 is folded towards anopposite side of the arm member 220 from the side on which the motor 210is positioned. The tip end portion 222 of the arm member 220 has aninsertion hole 223 formed therein, the leg gather 6 inserted into theinsertion hole 223.

In the present embodiment, the first swinging guide mechanism 200A andthe second swinging guide mechanism 200B are different in length of thearm members 220. The length L2 of the arm member 220 of the secondswinging guide mechanism 200B is longer than the length L1 of the armmember 220 of the first swinging guide mechanism 200A. On the otherhand, the distance from the press roller mechanism 130 to the tip endportion 222 of the first swinging guide mechanism 200A is the same asdistance from the press roller mechanism 130 to the tip end portion 222of the second swinging guide mechanism 200B. For this reason, therelationship between the above-described distance D1 and distance D2 isD2>D1.

For example, the length L1 of the arm member 220 of the first swingingguide mechanism 200A is 450 mm (see, FIGS. 5 to 7). On the other hand,the length L2 of the arm member 220 of the second swinging guidemechanism 200B is 600 mm (see, FIGS. 5 to 7).

Note that the length of the arm member 220 means here a length form thetip end portion 222 of the arm member 220 to the rotation shaft of thearm member 220.

The weight of the arm member 220 of the first swinging guide mechanism200A is 300 g. On the other hand, the weight of the arm member 220 ofthe second swinging guide mechanism 200B is 400 g.

The amplitude SW1 of the tip end portion 222 of the arm member 220 ofthe first swinging guide mechanism 200A along the cross direction CD is200 mm (see FIG. 4). On the other hand, the amplitude SW2 of the tip endportion 222 of the arm member 220 of the second swinging guide mechanism200B along the cross direction CD is 350 mm (see FIG. 4).

(5) Operation of Elastic Member Fixing Apparatus

(5-1) Overall Operation of Elastic Member Fixing Apparatus

Next, the operation of the elastic member fixing apparatus according tothe present embodiment will be described by referring to FIGS. 3 to 5.

The third web 7C is fed from the third web jumbo roll 7C′ by the upperweb feeding mechanism and the moving direction thereof is changed by theroller 140A. Onto a surface of the third web 7C whose moving directionis changed which faces to the second web 7B, an adhesive material isapplied by the upper adhesive applying mechanism 110A. At this time, theupper adhesive applying mechanism 110A applies an adhesive onto thesurface of the third web 7C except the center portion thereof. The thirdweb 7C onto which the adhesive is applied is supplied between the upperpress roller 130A and the lower press roller 130B from above.

Similarly, the second web 7B is fed from the second web jumbo roll 7B′by the lower web feeding mechanism and the moving direction thereof ischanged by the roller 140B. Onto the surface of the second web 7B whosemoving direction is changed which faces to the third web 7C, an adhesiveis applied by the lower adhesive applying mechanism 10B. The second web7B onto which the adhesive is applied is supplied between the upperpress roller 130A and the lower press roller 130B from below.

The elastic member 6 a′ is fed from the jumbo roll (unillustrated) bythe front gather feeding mechanism and is turned the moving directionthereof by the feed roller 150A. The elastic member 6 a′ turned by thefeed roller 150A is divided by the line-dividing roller 151A. Thedivided elastic member 6 a′ is swung by the first swinging guidemechanism 200A in the cross direction CD at a predetermined cycle.Accordingly, the elastic member 6 a′ is arranged in a curved shapebetween the second web 7B and the third web 7C to form the front leggather 6 a.

Similarly, the elastic member 6 b′ is fed from the jumbo roll(unillustrated) by the back gather feeding mechanism and is turned themoving direction thereof by the feed roller 150B. The elastic member 6b′ turned by the feed roller 150B is divided by the line-dividing roller151B. The divided elastic member 6 b′ is swung by the second swingingguide mechanism 200B in the cross direction CD at a predetermined cycle.Accordingly, the elastic member 6 b′ is arranged in a curved shapebetween the second web 7B and the third web 7C to form the back leggather 6 b.

The elastic member 6 a′ and the elastic member 6 b′ are pressed by theupper press roller 130A and the lower press roller 130B in a state ofbeing held between the second web 7B and the third web 7C onto which anadhesive is applied. For this reason, the elastic member 6 a′ and theelastic member 6 b′ are adhered between the second web 7B and the thirdweb 7C in a state of being swung by the swinging guide mechanism 120, sothat the above-described large ring portion 6C is formed. On the otherhand, even when the elastic member 6 a′ and the elastic member 6 b′ arearranged between the second web 7B and the third web 7C, the small ringportion 6 d is formed with the generation of resilience in the elasticmember 6 a′ and the elastic member 6 b′, since the adhesive is notapplied to the center portion of the third web 7C.

(5-2) Detailed Operation of Shaking Guide Mechanism

The operation of the swinging guide mechanism 120 will be described indetail by referring to FIGS. 4 and 6. The first swinging guide mechanism200A and the second swinging guide mechanism 200B are similarlycontrolled. Therefore, the description will be given by using the firstswinging guide mechanism 200A and the elastic member 6 a′ arranged bythe first swinging guide mechanism 200A.

In FIG. 4, the shaking guide mechanism 120 has the tip end portion 222from which the elastic member 6 a′ is fed. By using the arm member 220guiding the elastic member 6 a′, the tip end portion 222 is alternatelymoved in a first direction Da and in a second direction Db, the firstdirection Da directing from the center portion of the second web 7B(third web 7C) being conveyed in the conveyance direction MD to a firstend portion 7 a in the cross direction CD, and the second direction Dbdirecting from the center portion of the second web 7B (third web 7C) toa second end portion 7 b which is an end portion opposite to the firstend portion. Accordingly, the elastic member 6 a′ is brought intocontact between the second web 7B and the third web 7C to be arranged ina gather waveform (predetermined waveform).

In FIG. 4, the center line GL shows the center line of the gatherwaveform in the cross direction CD. In the present embodiment, anamplitude of the elastic member 6 a′ on the web in the second directionDb from the center line GL has a shorter cycle than that in the firstdirection Da.

The moving center ML of the tip end portion 222 is offset towards adirection having the shorter cycle of the amplitude, that is, to thesecond direction Db from the center line GL.

In the present embodiment, the tip end portion 222 forms a feedingportion and the arm member 220 forms a guiding portion. In addition, theconveyance direction MD forms a predetermined direction.

FIG. 6 is a schematic view for illustrating the movements of the elasticmember 6 a′ arranged on the web and the tip end portion 222 whicharranges the elastic member 6 a′ in the top view (a view seen from thedirection of the arrow A in FIG. 3) shown in FIG. 4. The waveform shownin FIG. 6 expresses the waveform of the elastic member 6 a′ arrangedbetween the second web 7B and the third web 7C and corresponds to thegather waveform of the front leg gather 6 a shown in FIG. 4. The solidline portion W1 expresses the waveform of the elastic member 6 a′ whichhas already been arranged between the second web 7B and the third web7C. The broken line portion W2 shows a designed position where theelastic member 6 a′ is to be arranged.

In the preset embodiment, in the planar view of the composite web 7, anip point N1 is a position in which the elastic member 6 a′ is broughtinto contact with the second web 7B and the third web 7C at time t1. Thetip end portion 222 is at least located at a feeding position P1 on thetangent at the nip point N1. At this time, a distance between the tipend portion 222 (that is, the feeding position P1) and the nip point N1is expressed by a feeding distance LN1.

In general, when the tip end portion 222 is arranged in the feedingposition P1 on the tangent to the gather waveform at the nip point N1,the elastic member 6 a′ can be arranged along the gather waveform.However, in the present embodiment, when the tip end portion 222 ismoving in the first direction Da, the tip end portion 222 is arranged ina marginal position m1 which is closer to the first end portion 7 a thanthe feeding position P1 on the tangent to the gather waveform at the nippoint N1. Similarly, when moving along the second direction Db, the tipend portion 222 is also arranged in a marginal position which is closerto the second end portion 7 b than a feeding position (unillustrated) onthe tangent to the gather waveform at the nip point.

In FIG. 6, a nip point N2 is a position in which the elastic member 6 a′is brought into contact with the second web 7B and the third web 7C attime t2. The nip point moves by the distance MD1 in the conveyancedirection MD from time t1. Here, the directions of the arrows MD1 showthe moving directions of the nip point and the tip end portion 222(feeding position) in relation to the second web 7B and the third web7C. The tip end portion 222 is at least located at a feeding position P2on the tangent to the gather waveform at the nip point N2.

Here, an angle φ between the tangent to the gather waveform at the nippoint N2 and the conveyance direction MD becomes the largest. That is,the nip point N2 is equal to an inflection point in the curved lineshowing the gather waveform. In the present embodiment, when the nippoint exceeds the position where the angle between the conveyancedirection MD and the tangent to the gather waveform becomes the largest(that is, at the nip point N2), the distance (feeding distance LN2)between the tip end portion 222 and the nip point becomes the largest.

That is, when the nip point exceeds the position (that is, at the nippoint N2) where the angle between the conveyance direction MD and thetangent to the gather waveform becomes the largest, the feeding distanceLN2 is larger than the feeding distance LN1.

When moving in the first direction Da, the tip end portion 222 isarranged in a marginal position m2 which is closer to the first endportion 7 a than the feeding position P2 on the tangent to the gatherwaveform at the nip point N2. Similarly, when moving along the seconddirection Db, the tip end portion 222 is also arranged in the marginalposition which is closer to the second end portion 7 b than the feedingposition (unillustrated) on the tangent to the gather waveform at thenip point.

In addition, in the present embodiment, a distance M between theposition on the tangent and the marginal position of the nip pointgradually becomes larger as the nip point moves from the position wherethe tangent to the gather waveform at the nip point is parallel to theconveyance direction MD, to the position where the angle between thetangent and the conveyance direction MD is largest. That is, in FIG. 6,the marginal distance M1<the marginal distance M2.

In contrast, a distance M between the position on the tangent to thegather waveform at the nip point and the marginal position graduallybecomes smaller (unillustrated) as the nip point moves, from theposition where the angle between the tangent to the gather waveform atthe nip point and the conveyance direction MD is largest, to theposition where the tangent is parallel to the conveyance direction MD.

In the present embodiment, it is preferable that the trajectory madealong the movement of the tip end portion 222 be a curved lineprojecting in at least the conveyance direction MD. Specifically, in thepresent embodiment, the tip end portion 222 is arranged in an arm havingthe rotational shaft in a predetermined position in relation to the web(gather waveform). That is, the tip end portion draws the arc-shapedtrajectory which crosses the conveyance direction MD.

Specifically, in the present embodiment, the swinging guide mechanism120 is a so-called swing arm swinging unit, which includes the motor 210having the rotational shaft 211, the arm member 220 guiding the elasticmember 6 a′ to a predetermined position between the second web 7B andthe third web 7C in the cross direction CD, the rotational shaft 211,and the base 221 of the arm member 220.

The tip end portion 222 from which the elastic member 6 a′ is fed isprovided at the tip end of the arm member 220. The arm member 220 isconnected with the motor 210 having the rotational shaft 211.Accordingly, the feeding position P1 which is the position of the tipend portion 222 and the marginal position m1 are arranged on an arc attime t=t1, the arc having its center at the rotational shaft 21 andhaving the length of the arm member 220 1 as a radius. Similarly, thefeeding position P2 and the marginal position m2 are also arranged on anarc at time t=t2, the arc having its center at the rotational shaft 211and having the length of the arm member 220 as a radius.

In the present embodiment, as shown in FIG. 4, an amplitude of theelastic member 6 a′ on the web to the second end portion 7 b from thecenter line GL of the gather waveform in the cross direction CD has ashorter cycle than that to the first end portion 7 a and the center ofthe movement of the tip end portion 222 is offset towards the curvatureof the short cycle of the amplitude from the center line GL.

Furthermore, it is preferable that the ratio W/L of the amplitude W ofthe elastic member 6 a′ on the composite web 7 to the first direction Daor the second direction Db and the length L of the arm member 220 bebetween 0.25 and 0.70, both inclusive.

In addition, in the present embodiment, the waveform made of the elasticmember arranged by the first swinging guide mechanism 200A and thewaveform made of the elastic member arranged by the second swingingguide mechanism 200B are different from each other. Moreover, the lengthof the arm member 220 provided in the first swinging guide mechanism200A and the length of the arm member 220 provided in the secondswinging guide mechanism 200B are different from each other.

In the present embodiment, as described above, the absorbent article 1is a wearing-type diaper, and the gather waveform in which the anglebetween the conveyance direction MD and the tangent to the gatherwaveform becomes the largest corresponds to an inguinal portion in theleg circumferential region of the diaper.

Specifically, as shown in FIG. 4, the gather waveform in which theelastic member 6 a′ is arranged by the first swinging guide mechanism200A corresponds to the waveform of the front leg gather 6 a. The regionSk shown in FIG. 4 corresponds to the portion where the angle betweenthe conveyance direction MD and the tangent to the gather waveformbecomes the largest. This region Sk corresponds to the inguinal portionof the wearer when the wearer puts on the diaper.

(6) Advantages and Effects

According to the elastic member fixing apparatus 100, in the planar viewof the composite web 7, the distance (feeding distance) in the crossdirection between the tip end portion 222 and the nip point is largerwhen the nip point exceeds the position where the angle between theconveyance direction MD and the tangent to the gather waveform becomesthe largest.

That is, in the planar view of the composite web 7, the tip end portion222 is arranged at a longer distance when the nip point exceeds theposition where the angle between the conveyance direction MD and thetangent to the gather waveform becomes the largest. The elastic member 6a′ is stretched by the tip end portion 222 to a distance more thandesigned, and thereafter, contracts to come closer to the web, and thencomes in contact with the web. Therefore, the elastic member 6 a′becomes easy to be arranged in a gather waveform.

Accordingly, according to the elastic member fixing apparatus 100,without requiring precise profile designing, the filiform elastic member6 a′ can be easily arranged in a desired position on the web, which isbeing conveyed at high speed, along the predetermined gather waveform.

In general, when the elastic member is arranged in the gather waveformon the web, in terms of the layout of the apparatus, it is not realisticthat the feeding position of the elastic member is brought into contactwith the nip point at which the elastic member comes in contact with theweb so as to accord the nip point with the feeding position of theelastic member from the feeding position. For this reason, a constantdistance is provided between the nip point and the feeding position ofthe elastic member 6 a′.

When the elastic member is to be arranged accurately along the gatherwaveform, at least the feeding position of the elastic member 6 has toalways be arranged on an extension of the tangent to the gather waveformat the nip point.

In addition, when the distance from the feeding position of the elasticmember to the nip point is long, even if the feeding position is notaccurately arranged on the tangent to the gather waveform at the nippoint, a range in which the elastic member can be arranged along thegather waveform is wide.

In the planar view of the composite web 7, when the nip point exceedsthe position where the angle between the conveyance direction MD and thetangent to the gather waveform becomes the largest, the distance betweenthe feeding position of the elastic member and the nip point becomeslarger. Therefore, the elastic member fixing apparatus 100 can have awider tolerance range.

Accordingly, according to the elastic member fixing apparatus 100,without requiring precise profile designing, the filiform elastic member6 a′ can be easily arranged in a desired position on the web, which isbeing conveyed at high speed, along the predetermined gather waveform.

In the elastic member fixing apparatus 100, when the tip end portion222, which is the feeding position of the elastic member 6 a, is movingin the first direction Da, the tip end portion 222 is arranged in themarginal position m1 which is closer to the first end portion 7 a thanthe tangent to the gather waveform at the nip point. In addition, whenthe tip end portion 222 is moving in the second direction Db, the tipend portion 222 is arranged in the marginal position which is closer tothe second end portion 7 b than the tangent to the gather waveform atthe nip point.

Furthermore, the distance M between the position on the tangent to thegather waveform and the marginal position m1 at the nip point graduallybecomes larger, as the nip point moves, from the position where thetangent is parallel to the conveyance direction MD, to the positionwhere the angle between the tangent and the conveyance direction MD islargest. In addition, the distance to the position on the tangent to thegather waveform at the nip point becomes gradually smaller as the nippoint moves, from the position where the angel between the tangent andthe conveyance direction MD is largest, to the position where thetangent is parallel to the conveyance direction MD.

In this manner, the distance from the feeding position of the elasticmember 6 a′ to the nip point can be set to be large in a vicinity of theposition where the angle between the tangent and the conveyancedirection MD becomes the largest. Therefore, the elastic member fixingapparatus 100 can have a wider tolerance range.

Accordingly, according to the elastic member fixing apparatus 100,without requiring precise profile designing, the filiform elastic member6 a′ can be easily arranged in a desired position on the web, which isbeing conveyed at high speed, along the predetermined gather waveform.

In the elastic member fixing apparatus 100, an amplitude of the elasticmember 6 a′ on the web in the second direction Db from the center lineGL of the gather waveform (predetermined waveform) in the crossdirection CD has a shorter cycle than that in the first direction Da andthe center ML of the movement of the tip end portion 222 is offsettowards a direction having the shorter cycle of the amplitude from thecenter line GL.

For this reason, deviation in the moving amounts of the tip end portion222 to the first direction and the second direction can be reduced.Accordingly, the feeding position of the elastic member 6 a′ can moreprecisely track the gather waveform.

In the present embodiment, the trajectory made along the movement of thetip end portion 222 is a curved line projecting in at least theconveyance direction MD, so that the tip end portion 222 provided at thetip end of the arm member 220 moves on the curved line projecting in theconveyance direction MD. This causes a difference in distance betweenthe tip end portion 222 and the nip point in the conveyance direction MDin addition to the distance therebetween in the cross direction CD.Therefore, the distance (feeding distance) from the feeding position ofthe elastic member 6 a′ to the nip point can be extended in theconveyance direction MD. Thus, the tolerance range can be furtherwidened.

Accordingly, without requiring precise profile designing, the filiformelastic member 6 a′ can be easily arranged in a desired position on theweb, which is being conveyed at high speed, along the predeterminedgather waveform.

In the present embodiment, the swinging guide mechanism 120 includes themotor 210 having the rotational shaft 211, the arm member 220 guidingthe elastic member 6 a′ to a predetermined position in the crossdirection CD between the second web 7B and the third web 7C, therotational shaft 211, and the base 221 of the arm member 220.

As described above, when the arm member 220 rotates, the tip end portion222 provided in the tip end of the arm member 220 draws an arc-shapedtrajectory. For this reason, on the both ends of the arc, a differencein distance between the feeding position and the nip point is also madein the conveyance direction MD in addition to the distance therebetweenin the cross direction CD. Therefore, the distance (feeding distance)from the feeding position of the elastic member 6 a′ to the nip pointcan be extended in the conveyance direction MD. Thus, the tolerancerange can be further widened.

Accordingly, without requiring precise profile designing, the filiformelastic member 6 a′ can be easily arranged in a desired position on theweb, which is being conveyed at high speed, along the predeterminedgather waveform.

In the present embodiment, a ratio W/L of the amplitude W of the elasticmember on the web to the first direction Da or the second direction Dband the length L of the arm member 220 is set to be between 0.25 and0.70 both inclusive. Accordingly, the distance (feeding distance) fromthe feeding position to the nip point can be properly set and theelastic member 6 a′ can be arranged along the gather waveform withoutrequiring precise profile designing.

In the present embodiment, the swinging guide mechanism 120 includes onepair of the first swinging guide mechanism 200A and the second swingingguide mechanism 200A, and the waveform in which the elastic member 6 a′is arranged by the first swinging guide mechanism 200A and the waveformin which the elastic member 6 a′ is arranged by the second swingingguide mechanism 200B are different waveforms. In addition, the length ofthe arm member provided in the first swinging guide mechanism 200A andthe length of the arm member provided in the second swinging guidemechanism 200B are different from each other.

With this configuration, multiple elastic members can be respectivelyarranged along different gather waveforms on one web which is conveyedin the conveyance direction MD at a conveyance speed V1.

In the present embodiment, the absorbent article 1 is a wearing-typediaper, and the gather waveform in which the angle between theconveyance direction MD and the tangent to the gather waveform becomesthe largest corresponds to the inguinal portion in the leg circumferenceregions of the diaper. The region corresponding to the inguinal portionis the most important portion, which determines whether or not theproduct is comfortable to put on.

The elastic member fixing apparatus 100 can have a wider tolerance rangebecause the distance from the feeding position to the nip point can beset to be longer when the elastic member 6 a′ is arranged in theposition where the angle between the tangent and the conveyancedirection MD becomes the largest, that is, in the region Skcorresponding to the inguinal portion.

Accordingly, without requiring precise profile designing, the elasticmember 6 a′ can be accurately arranged in the position corresponding tothe inguinal portion in which accuracy of the product is most demanded.

(7) Other Embodiments

As described above, the content of the present invention has beendisclosed by using the embodiment of the present invention. However, itshould not be understood that the description and drawings whichconstitute one part of this disclosure limit the present invention. Fromthis disclosure, various alternative embodiments, examples, andoperational techniques will be apparent for a person skilled in the art.

For example, the embodiment of the present invention can be modified asfollows. Specifically, the manufacturing method of an absorbent articleand the elastic member fixing apparatus are not limitedly applicable tothe absorbent article 1 (so-called disposable diaper) provided with thefront waistline region 10, the back waistline region 20, the crotchregion 30, and the like, but can be applicable to various articles suchas disposable gowns for medical use and disposable wears for sports.

In addition, the elastic member, which is a component forming theabsorbent article 1, has been described as being formed of an elasticfiliform rubber or the like. However, the elastic member is not limitedto this and may be formed of a flat rubber, a sheet-like rubber, or thelike.

Moreover, the elastic member does not have to be a rubber. For example,the elastic member may be a resilient or elastic fiber such as polyesteror polyurethane. The elastic member may be an elastic fiber other thanthese fibers. Some of these fibers may be used by being stranded.

In addition, the first swinging guide mechanism 200A and the secondswinging guide mechanism 200B are described to have the arm members 220with different lengths from each other. However, the lengths thereof arenot limited to this but may be the same length.

In addition, the program operating the motor 210 of the first swingingguide mechanism 200A is described to be different from the programoperating the motor 210 of the second swinging guide mechanism 200B.However, the configuration is not limited to this, and the programoperating the motor 210 of the first swinging guide mechanism 210 may bethe same as the program operating the motor 210 of the second swingingguide mechanism 200B. That is, the predetermined extension magnificationor the layout in the front leg gather 6 a may be same as thepredetermined extension magnification or the layout in the back leggather 6 b.

In addition, the insertion hole 223 into which the leg gather 6 isinserted is described to be formed in the tip end portion 222 of the armmember 220. However, the configuration is not limited to this. The tipend portion 222 only needs to guide the leg gather 6. For example, aU-shaped groove may be formed therein.

In the present embodiment, the swinging guide mechanism 120 is describedto include the motor 210 having the rotational shaft 211, the arm member220 guiding the elastic member 6 a′ to a predetermined position in thecross direction CD between the second web 7B and the third web 7C, therotational shaft 211, and the base 221 of the arm member 220. However,it is not limited to the configuration in which the arm member 220rotates around the rotational shaft.

For example, the guiding unit having the feeding position from which theelastic member 6 a′ is fed may be a mechanism moving in a movement rangeregulated by an arc-shaped slide rail, an arc-shaped rib, an arc-shapedcam groove and a cam follower, or the like. Driving means applicable tothis case includes, for example, a timing belt, a link joint, anarc-shaped linear servo, or the like.

In this manner, as a matter of course, the present invention includesvarious embodiments which are not described herein. Accordingly, thetechnical scope of the present invention is defined only by theparticular matters contained in the scope of claims which is appropriatefrom this disclosure.

1. An apparatus for manufacturing an absorbent article, said apparatuscomprising: a guide mechanism for guiding elastic members, said guidemechanism having first and second swinging arm members with feedingportions respectively for feeding the elastic members, and first andsecond motors having rotational shafts at bases of the first and secondarm members respectively and configured to swing the first and secondarm members in a cross direction at predetermined cycles, wherein theguide mechanism is configured to move the feeding portions alternatelyin a first direction and a second direction so that the elastic membersare brought into contact with a web conveyed in a machine directionsubstantially perpendicular to the cross direction and are arrangedrespectively in first and second predetermined waveforms, the firstdirection directing from a center portion of the web to a first endportion in the cross direction, and the second direction directing fromthe center portion to a second end portion opposite to the first endportion in the cross direction, and wherein in a planar view of the web,each of the first and second arm members is configured to move therespective feeding portion so that a distance between the feedingportion and a nip point at which the elastic member comes in contactwith the web becomes largest when the nip point is at a position in therespective predetermined waveform where an angle between the machinedirection and a tangent to the predetermined waveform is largest, eachof the first and second arm members is configured to move, when movingthe respective feeding portion in the first direction, the feedingportion in a first marginal position located closer to the first endportion than an intersection of (i) the tangent to the respectivepredetermined waveform at the nip point and (ii) an arc defined by therespective arm member, and each of the first and second arm members isconfigured to move, when moving the respective feeding portion in thesecond direction, the feeding portion in a second marginal positionlocated closer to the second end portion than the intersection of (i)the tangent to the respective predetermined waveform at the nip pointand (ii) the arc defined by the respective arm member, wherein the firstand second predetermined waveforms defined by the first and second armmembers respectively are different from each other, a length of thefirst arm member is different from that of the second arm member, and adimension between the base and the feeding portion of the first armmember is unequal to that between the base and the feeding portion ofthe second arm member in the machine direction.
 2. The apparatusaccording to claim 1, wherein each of the first and second arm membersis configured to move the respective feeding portion, so that a distancebetween the position on the tangent to the respective predeterminedwaveform at the nip point and the first marginal position becomesgradually larger as the nip point moves from a position where thetangent is parallel to the machine direction, toward the position wherethe angle between the tangent and the machine direction is largest. 3.The apparatus according to claim 1, wherein each of the first and secondarm members is configured to move the respective feeding portion, sothat a distance between the position on the tangent to the respectivepredetermined waveform at the nip point and the second marginal positionbecomes gradually smaller as the nip point moves from the position wherethe angle between the tangent and the machine direction is largest,toward a position where the tangent is parallel to the machinedirection.
 4. The apparatus according to claim 1, wherein each of thefirst and second arm members is configured to move the respectivefeeding portion, so that an amplitude of the respective elastic memberon the web in one of the first and second directions from a center lineof the respective predetermined waveform in the cross direction has ashorter cycle than that in the other direction, a center of movement ofthe respective feeding portion is offset from the center line in thedirection having the shorter cycle of the amplitude.
 5. The apparatusaccording to claim 1, wherein each of the feeding portions is moveablealong the respective arc projecting in at least the machine direction.6. The apparatus according to claim 1, wherein a ratio W/L of anamplitude W of one of the elastic members on the web in the firstdirection or the second direction and a length L of the respective armmember is between 0.25 and 0.70 both inclusive.
 7. The apparatusaccording to claim 1, wherein the absorbent article is a diaper, and theposition on one of the first and second predetermined waveforms in whichthe angle between the machine direction and the tangent to thepredetermined waveform is largest is for an inguinal portion in a legcircumferential region of the diaper.
 8. The apparatus according toclaim 1, wherein the first arm member is configured to move therespective feeding portion, so that an amplitude of the feeding portionof the first arm member from the center line of the first predeterminedwaveform to the first end portion in the cross direction is greater thanthat that from the center line of the first predetermined waveform tothe second end portion in the cross direction.
 9. The apparatusaccording to claim 8, wherein the second arm member is configured tomove the respective feeding portion, so that an amplitude of the feedingportion of the second arm member from the center line of the secondpredetermined waveform to the first end portion in the cross directionis greater than that that from the center line of the secondpredetermined waveform to the second end portion in the cross direction.10. The apparatus according to claim 9, wherein each of the first andsecond arm members is configured to move the respective feeding portion,so that the amplitude of the feeding portion of the first arm member inthe cross direction is less than the amplitude in the cross direction ofthe feeding portion of the second arm member.
 11. The apparatusaccording to claim 10, wherein the length of the first arm member isless than that of the second arm member.
 12. An apparatus formanufacturing an absorbent article, said apparatus comprising: a guidemechanism for guiding elastic members, said guide mechanism having firstand second swinging arm members with feeding portions respectively forfeeding the elastic members, and first and second motors havingrotational shafts at bases of the first and second arm membersrespectively and configured to swing the first and second arm members ina cross direction at predetermined cycles, wherein the guide mechanismis configured to move the feeding portions alternately in a firstdirection and a second direction so that the elastic members are broughtinto contact with a web conveyed in a machine direction substantiallyperpendicular to the cross direction and are arranged in predeterminedwaveforms, the first direction directing from a center portion of theweb to a first end portion in the cross direction, and the seconddirection directing from the first end portion to a second end portionopposite to the first end portion in the cross direction, and wherein ina planar view of the web, each of the first and second arm members isconfigured to move, when moving the respective feeding portion in thefirst direction, the feeding portion in a first marginal positionlocated closer to the first end portion than an intersection of (i) thetangent to the predetermined waveform at the nip point and (ii) an arcdefined by the respective arm member, and each of the first and secondarm members is configured to move, when moving the respective feedingportion in the second direction, the feeding portion in a secondmarginal position located closer to the second end portion than theintersection of (i) the tangent to the predetermined waveform at the nippoint and (ii) the arc defined by the respective arm member, wherein adimension between the base and the feeding portion of the first armmember is unequal to that between the base and the feeding portion ofthe second arm member in the machine direction.